1. Field of the Invention
The present invention relates to a dynamic vibration absorber for a disk player, and more particularly, to a dynamic vibration absorber for a disk player that reduces vibration generated when a recording medium spins.
2. Description of the Related Art
Generally, a disk player is an apparatus that records and/or reproduces information to and from a disk such as a compact disk (CD), a CD-Rom, a digital video disk (DVD), a DVD-Rom, a CD-RW, and a combo disk. This apparatus needs to protect the disk and an optical pickup therein from both outer shock and inner vibration.
A conventional disk player generally includes a deck base disposed in a housing of the disk player, a deck plate movably disposed on the deck base, a spindle motor disposed on the deck plate to generate energy to spin the disk, a turn-table connected to a pivot shaft of the spindle motor to support the disk, a damper disposed at the upper part of the housing corresponding to the turn-table to clamp the disk on the turn-table, and an optical pickup movably connected to the deck plate to move radially across the disk to record and/or reproduce information to and from the disk. In the above construction, a buffering member is disposed between the deck base and the deck plate to protect the disk and the optical pickup from an outer shock.
However, since the centers of rotation and gravity of a conventional disk do not always correspond due to manufacturing errors, an inner vibration results and generates whirling. Because of the inner vibration, it is difficult to prevent the generation of idle revolution of a rotating shaft of the spindle motor.
Due to this problem, an auto-ball-balancer has been developed to balance an eccentric mass by setting up balls at opposite side of the mass eccentricity. The auto-ball-balancer includes a circular accommodating portion in a spinning body like the turn-table and the spindle motor, and the auto-ball-balancer is realized by placing balls having a predetermined mass in the accommodating portion. However, the auto-ball-balancer is only effective in balancing an eccentric disk. In addition, when the auto-ball-balancer is applied to the eccentric disk, the auto-ball-balancer also causes a problem by increasing the vibration in a resonance band.
In addition, although a deck plate is well balanced, it possesses a natural frequency in accordance with its design and material. Thus, when vibration is generated around the natural frequency, there is a problem of an increased vibration due to a resonance effect. In this case, it is difficult for the optical pickup to record and/or reproduce data to and from the disk. Due to this problem, there is a limitation in the increase in recording density of the disk. Moreover, the vibration can dramatically affect peripheral devices such as a hard disk drive (HDD) and a floppy disk drive (FDD).